DENVER — June can be the most active weather month in Colorado when warm, moist air feeds up from the south and collides with cool, dry air from the northwest, sometimes spawning tornadoes.
Being right on the edge of Tornado Alley, Colorado typically sees about 45 to 50 tornadoes a year, the bulk of which occur during June and barely register on the Enhanced Fujita Scale (EF Scale). But the state has seen its fair share of some vicious twisters—some wiping entire towns off the map.
The overwhelming majority of these storms occur along the Front Range and in Eastern Colorado. However, tornadoes have touched down in other parts of the state, including mountain communities.
Redstone tornado
What was the largest tornado to ever touch down in western Colorado? An F2 tornado touched down near the area of Redstone in Pitkin County on June 20, 1975. No injuries or damages were reported.
Mount Evans tornado
A rare mountain tornado touched down on Mount Evans at an elevation of 11,900 feet on July 28, 2012. The Denver Post reported, that meteorologists were "investigating a tornado reported Saturday on Mount Evans that could be the second highest ever recorded in the country."
Tornadoes on the Eastern Plains tend to be stronger. EF3 or higher tornadoes have not been reported in the high country or on the Western Slope of Colorado. An EF-3 will take roofs off houses, do a lot of damage to buildings, blow all the windows out of cars or flip them over. EF3 tornadoes see winds of 136 to 165 mph.
Here is the EF scale:
EF0...Weak......65 to 85 MPH
EF1...Weak......86 to 110 MPH
EF2...Strong....111 to 135 MPH
EF3...Strong...136 to 165 MPH
EF4...Violent...166 to 200 MPH
EF5...Violent...>200 MPH
Limon tornado
On June 6, 1990, one of the strongest tornadoes to occur in the state struck the town of Limon. Fourteen people were injured but no one was killed. The F3 tornado destroyed several buildings as it tore through the downtown area.
Windsor tornado
An EF3 tornado carved a nearly 39-mile-long path of destruction in Weld County near the town of Windsor on May 22, 2008. Seventy-eight people were injured, and one person was killed trying to escape a trailer park in his motor home. The tornado, up to one mile wide at times, initially touched down northeast of Platteville and finally lifted six miles west-northwest of Wellington, according to the National Weather Service.
Thurman tornado
The deadliest tornado in Colorado happened on August 10, 1924, in the Washington County town of Thurman, which once had a population of over 150 people. The tornado struck a farm four miles east of the town where a local gathering was going on, killing 10 people, many of whom were children. The tornado was estimated to have been 1/2 mile wide and may have been an EF4, according to the NWS. The 1924 event is thought to be the strongest tornado to hit Colorado on record.
Last Chance tornado
Five tornadoes touched down near the area of Last Chance in Washington County on July 21, 1993. No one was injured or killed, but the storms damaged several farms in the area.
Berthoud tornado
The largest tornado (on record) to affect Boulder and Larimer counties occurred on June 4, 2015. The EF3 tornado near the town of Berthoud was a quarter-mile wide at times with estimated wind speeds up to 140 mph. Twenty-eight homes were damaged with three being destroyed. No injuries or deaths occurred.
Although not as common compared to the Eastern Plains, Denver is not immune to the storms that produce tornadoes. The biggest tornado event that struck Denver was on June 15, 1988.
1988 Denver tornado
Seven people were injured when an F-3 tornado touched down in the southern part of the city, cutting an erratic path 2.5 miles long on June 15, 1988. The storm damaged 85 buildings and several cars and uprooted trees.
The injuries were minor, but according to NWS reports, very traumatic for some of those involved. A golfer was thrown 40 feet but was not hurt. A man clinging to a telephone pole was unscathed but lost both of his shoes. A woman holding a baby was sucked through a broken window of a convenience store, but neither the woman nor the baby was hurt.